1. Field of the Invention
This invention relates to methods and apparatus for recording signals on video tape, and particularly to a method and apparatus for recording instrument quality data on a conventional unmodified video tape recorder while utilizing the conventional video composite waveform.
2. Description of the Prior Art
We are not aware of any patents, domestic or foreign that address the problem of recording instrument quality data on commercially available conventional video tape using a conventional unmodified video tape recorder while utilizing the conventional video composite waveform. In like manner, we are not aware of any periodical literature that addresses this problem or proposes a solution to the problem.
To understand the problem, and the solution, it is well to review briefly the cooperative relationship which exists between conventional unmodified video tape recordings and video or television (TV) sets or TV monitors on which the images recorded by the video tape recorder are displayed. It is important to keep in mind that essentially all television sets manufactured in the United States or imported into the United States from foreign manufacturers conform to the same conventional video composite waveform standard. Video composite waveform may be defined as analog signals (normally video signals) recorded on video tape in a series of transversely extending tracks spaced longitudinally from one another, thus introducing a series of discontinuities, requiring the synchronization of the recorded analog signals by use of vertical and horizontal synchronization pulses also recorded on the video tape, but recorded thereon in tracks that extend longitudinally of the video tape. Conformation of all TV sets and video tape recorders to this conventional video composite waveform standard is important because it forms the basis for compatibility among the many different brands of television sets and video tape recorders.
Heretofore, audio or other analog or digital signals have been recorded on magnetic tape by conventional magnetic tape recorders only on elongated tracks running parallel to the longitudinal dimension of the recording tape. So far as we know, data signals, either analog or digital, have never been recorded on conventional video tape utilizing a conventional unmodified and commercially available video tape recorder which utilizes the video composite waveform standard so that such data signals are recorded on the video tape in discontinuous tracks that extend transversely across the video tape.
Accordingly, one of the important objects of this invention is the provision of a method of recording instrument quality data signals on a recording medium including magnetic material in a pattern compatible to the conventional video composite waveform standard.
Another object of the invention is the provision of a method of recording instrument quality data on video tape through use of a conventional unmodified video tape recorder the operation of which adheres to the conventional video composite waveform standard.
Still another object of the invention is the provision of a method of recording instrument quality data signals on video tape directly or indirectly using a modulated carrier wave.
A still further object of the invention is the provision of apparatus for selectively recording instrument quality data, or composite instrument quality data and video signals on a commercial unmodified video tape recorder.
The invention possesses other objects and features of advantage, some of which, with the foregoing, will be apparent from the following description and the drawings. It is to be understood however that the invention is not limited to the particular method or means illustrated and described, since it may be embodied in different forms within the scope of the appended claims.